Cooling devices for the cement clinkers



Sept. 15, 1959 F, CQVA ET AL COOLING DEVICES FOR THE CEMENT CLINKERSFiled April 5. 1957 2 Sheets-Sheet l F. covA ETAL COOLING DEVICES RORTHE CEMENT CLINKERS Sept. 15, 1959 2 Sheets-Sheet 2 Filed April 5, 1957INVENToRs FEDELE COVA, SERGIO DE AMICIS, CESARE CESAREN| BY MM al gil/0MATTORNEYJ` @EON SIQCS atento COOLING DEVICES 'FOR THE CEMENT-.CLINKERSFedele Cova, Sergio De Amicis, land Cesare -'Cesareni, .Rome, t Italy,.assignors :to `Cementir .Cementerie 'Del Tirreno S.p.A., Rome, Italy, acompany of Italy Application April 5, 1957, Serial No,. 6570,943 Claimspriority, application Italy-April 20,1956 2 Claims. (Cl. 263-32) It isknown that the cooling Vgratesr for the cement .clinkers operate lbymeans of ya cold air insutllation through a layer of clinker arranged ona movable grate plane.

It is also known that when, due to particular chemical -orphysico-chemical features of the -raw material, or due Vto a particularoperation of -the kiln, a clinker is produced -which is not perfectlyagglomerated to grains having a certain size, the good operation of thecooling grate is adversely affected by the following co-acting causes:

Diminution of the permeability ofthe layer arranged on the grate andconsequent abnormal over-heating of `clinker between the movable andthestationary parts, the `operation of the unit being alsofrendered moresevere by .the lesser cooling due to the lesser passage of airconsequent to the reduced permeabilityofthe clinker layer.

.Diicult operation of the kilnin that when the powder vconditions of theclinker change, also-the permeability of the layer arranged on the gratechanges, and with it the air amount fed over thev grate.

The clinker cooling occurs irregularly andvparticularly in response to agreater or lesser permeability of the layer arranged on the grate, atparity of kiln output.

The object of the present invention is the separation and the removal ofthe powder fraction of the clinker at its outlet from the kiln beforesaid powder fraction comes into contact with the grate plane.

The above separation of the powder fraction from the clinker grains maybe obtained by means of a strong air stream blown by a blower through anaperture arranged over the head of the grate, under the outlet from thekiln. Said aperture is so arranged that the air stream issuing therefrompasses through the tlow of incandescent clinker falling from thefurnace, carrying out the particles having a lesser mass, i.e. lthesmaller particles.

By adjusting the blower rate and the size of the aforesaid aperture itis possible to adjust the unit so as to remove only those particleshaving a diameter smaller than that which can be considered prejudicialtoa good operation of the grate, so that only the greater diameteredgrains reach the grate, i.e. those forming thereon a surely permeablelayer.

As the air blown through the aperture is cold air, a rapid cooling isobtained for the smaller particles which are removed by the air stream.

The smaller clinker particles carried by the air stream are recovered inla separator device and conveyed to the outlet from the grate, wheresaid particles are mixed to the cold granular clinker which leaves thegrate.

The device may be embodied in any suitable way so as to be applied toany type of cooling grate.

This invention will be diagrammatically described by `way of example,

Patented Sept. v15, 1959 2 with referencel to' the attached drawings,wherein:

Fig. lshowspa 4diagrammaticral.vertical cross-sectional view of a plantwith. a removable plates grate, embodying the improvement according tothisinvention, and

Fig. 2.shows a detail perspective view, in anenlar'ged scale, of thefeeding and blowing systemfor theair 'to remove the powder fraction ofthe product.

,Fig. 3 is a detail view of the grate plates.

It isto be noted that, although Fig. l shows, even vif in largelydiagrarnmaticalI form, the wholejproduction plant for the clinkeronlytheparts concerned with this invention will be hereinafter described.

The device comprises the rotary type kiln 1, rediby the burner 12; saidfurnacedelivers through the outlet 13 the incandescent clinker whichfalls into the chamber y14, the bottom of which isformed by the movableplates grate 6.

The fall of the clinker passesgthrough the cool air streamr2,issuinglfrom theaperture 3.and which will be described in morevdetailhereinafter. Said stream passes lengthwise through the chamber 14, overthe grate 6, vand is supplied by the blower 4.

The larger particles, due to their own weight, pass through Vsaid streamL2 and Vfall then onto the planel of the grate `6, while the lessdiametered particles, generally shown at 7 inFig. l,v are conveyed bythe stream 2.towards the flue 1,5 wherefrom said particles enter thecyclone separator'S where the clinker is separated from the air, thelatter ybeing exhausted towards the flue 11,

`duelo the sucking actionof thefan 10, while the sepa- .rated clinkerparticlesfallto the outlet from the grate 9.

With reference'to Fig. 2, although for sake of clearness in the drawingtheproportions of some parts have been altered, also .in this figure, 4denotes the blower delivering the air to the aperture 3 forming theoutlet of agprismatic.header:17 n extending throughout the lengthcorresponding to the fall of the clinker, so as to have an air streamimpinginggagainstthe full width of said fall.

An adjustingvmeans for the air delivery is inserted within the 'aperture3, and said means consists of a tapered flap 18, the thinner edge ofwhich is substantially flush with the inner wall 20 of the chamber 40,while the thicker edge is pivoted at 19 on the prismatic header 17.Thus, by rotating the flap 18 by means of any known device, not shown infigure, it is possible to adjust the amount of the air issuing from theaperture 3, and therefore to adjust fthe conveying action on theclinker. The grate schematically illustrated in Fig. 1 of the drawing isshown in Fig. 3 as being formed of a stationary (A) and a movable (B)frame. On the two frames there are mounted alternately rows of steppedplates having on one side an upper plane (C) inclined upwardly at a fewdegrees relative to the horizontal from the end of the incoming materialand having an almost vertical projection (D) on the opposite side. Theplates mounted on the movable frame are reciprocated by the frame. Whenadvancing toward the discharging outlet the vertical projection urgesthe material in the same direction and conveys it on the stationaryplates. When the plates return to the starting position, on thecontrary, the material slides on the inclined plate without followingthe motion thereof. In this manner the material is given a pulsatingmotion toward the outlet.

We claim:

l. A cooling device for cement clinkers supplied by a kiln, whichcomprises a cooling chamber for the clinker, a rotating kiln associatedwith the said chamber and opening into said cooling chamber to supplythe clinker thereto, said chamber having an inlet at the end thereofwhich receives the clinker supplied by the said kiln, said chamberhaving a first outlet in the lower part of the said chamber at the endopposite the said inlet and a second outlet in the upper wall of thechamber at the ,same end as the said first outlet, a lgrate located inthe lower partof the said. chamber for receiving theclinker receives theclinker having an aperture therein intermediate between the said inletand the said`grate, a Y

blower connected to the said aperture outside of the said chamber forsupplying cold air to said chamber through the said aperture, saidaperture being adjustable in area and being positioned to direct saidcold air against the t falling `clinker supplied by said kiln beforesaid clinker reaches the said grate, whereby the clinker having smalldimensions is prevented from reaching said grate and is removed togetherwith the air supplied by the said blower through said chamber along azone located above the said grate toward the said second outlet, meansexternal of the said chamber and located at the end of the chamber inwhich the two outlets are located for joining externally of the saidchamber the two outlets, whereby the particles of small dimensions ofthe clinker coming out of the said second outlet are mixed with theclinker of large dimensions coming out of the said rst outlet.

2. A cooling device for cement clinkers supplied by a kiln, whichcomprises a cooling chamber for the clinker, a rotating kiln associatedwith the said chamber and opening into said cooling chamber to supplythe clinker thereto, said chamber having an inlet at the end thereofwhich receives the clinker supplied by the said kiln, said chamberhaving a first outlet in the lower part of the said chamber at the endopposite the said inlet and a second outlet in the upper wall of thechamber at the same end as the said first outlet, a grate located in thelower part of the said chamber for receiving the clinker suppliedthrough the said inlet, said grate being for conveying the clinker whichhas fallen thereon toward the lsaid rst outlet, means associated withand located underneath the said grate for forcing cooling air throughthe said |grate and the clinker which has fallen on the grate, the wallof the said chamber at the end which receives the clinker having anaperture therein intermediate between the said inlet and the said grate,said aperture having a length adapted to extend across the width of themass of the clinker falling from the said rotating kiln on the grate, ablower connected to the said aperture outside of the said chamber forsupplying cold air through the said aperture to the said chamber, aheader having a trapezoidal section connected on one end to the saidblower and extending into the said aperture ush with the inner surfaceof the said chamber along the whole width of the said aperture, atapered flap having a length equal to the inner length of the header andbeing pivoted at its rear edge on the said header at the outer surfaceof the forewall of the said chamber and having the free end ush with theend of the header at the inner surface of the chamber, said ap beingmovablev to vary the section of the said header opening into the saidchamber, said header being positioned to direct said cold air againstthe clinker falling from said rotating furnace before the clinkerreaches the said grate, whereby the particles of the clinker of smalldimensions are prevented from reaching the said grate and are removedtogether with the air stream coming from the said header along a zonelocated above said grate toward the said second outlet, a cyclonelocated near and connected to the said second outlet and receiving saidair containing the particles of clinker of small dimensions andseparating said particles from the said air and for said particles tofall down and join the said clinker with large dimensions coming fromthe said first outlet.

References Cited in the tile of this patent UNITED STATES PATENTS127,727 Yeagly June 1l, 1872 1,420,593 Titchmarsh June 20, 19221,837,836 Powell Dec. 22, 1931 2,346,500 Moorev Apr. 11, 1944 2,587,378Petersen Feb. 26, 1952 2,750,681 Berry June 19, 1956 FOREIGN PATENTS296,221 Great Britain Aug. 30, 1928

